Optical discs are widely used as a recording medium for recording mass data. Presently, among a wide range of optical discs, a new high density optical recording medium, such as a blu-ray disc (hereinafter referred to as “BD”), is under development for recording (or writing) and storing high definition video and audio data for a long period of time. The blu-ray disc (BD), which is known to be the next generation recording medium technology, is also considered to be a next generation optical recording solution that is capable of having data significantly surpassing the conventional DVD. And, recently, optical recording and/or reproducing apparatuses for recording and/or reproducing the blu-ray disc (BD) has been under development.
Most particularly, in the above-described optical recording and/or reproducing apparatus, the basic function(s) of recording and/or reproducing the blu-ray disc (BD), as well as additional functions taking into account a combined usage with related peripheral digital apparatuses are/is being considered. Thus, generally, the optical recording and/or reproducing apparatus must be provided with functions of either receiving external input signals and displaying the received signals, or applying external input signals with a built-in blu-ray disc (BD) playback signal for reproduction.
However, since preferable playback (or reproducing) methods for reproducing a binding of the external input signal and the built-in blu-ray disc (BD) playback signal are not yet known and familiarized, there are many restrictions in the full-scale development of a blu-ray disc (BD)-based optical recording and/or reproducing apparatus. And, such restrictions cause problems in the field of reproducing the external input signal and the built-in blu-ray disc (BD) playback signal as one single reproducing unit.